A new method for the fixation of sound-conducting elements of the middle ear during ossiculoplasty

The objective of the present work was to estimate the possibilities of the application of platelet-enriched plasma as a filtering material for ossiculoplasty. The results of surgical interventions on 120 patients presenting with chronic suppurative otitis media are reported. All the patients underwent closed-type sanation surgery (differential atticoanthrotomy) including either complete or partial restoration of the sound conduction mechanism in the middle ear. Platelet-enriched plasma was applied into the tympanic cavity of 55 patients as a fixing material for the reconstruction of the chain of the auditory ossicles. Ossiculoplasty without additional fixation was performed in 65 patients comprising the control group. The results of the study indicate that a clot of platelet-enriched plasma may be a good fixing material for the reconstruction of the entire chain of auditory ossicles and can be used for all types of ossiculopasty.     

Hyaluronic acid reduces connective tissue formation in middle ears filled with absorbable gelatin sponge: an experimental study

Absorbable gelatin sponge, commonly used in otosurgery, was mixed with high-molecular-weight, highly concentrated hyaluronic acid. The mixture was introduced into the middle ear cavities of rats. The postoperative changes were evaluated by morphologic techniques after two months and three months. The middle ear cavity contained a loose mass of connective tissue with few cells, forming sail-like bridles between air-filled spaces. The filling material was easily detached from the surroundings. The structure of the middle ear mucosa and the tympanic membrane was well preserved. Compared with the findings in a previous study, in which absorbable gelatin sponge alone was used, the combination of gelatin sponge and hyaluronic acid caused significantly less structural alterations in the middle ear cavity. It is concluded that hyaluronic acid, a natural component in most tissues, markedly reduces the formation of the fibrous connective tissue known to develop in middle ear cavities filled with absorbable gelatin sponge alone.     

Acute otitis media develops in the rat after intranasal challenge of Streptococcus pneumoniae

OBJECTIVES/HYPOTHESIS: The rat is a frequently used animal model for middle ear research. To date, acute otitis media (AOM) has been evoked after instillation of bacteria directly into the middle ear cavity or after traumatizing the tympanic membrane. The purpose of the study was to examine whether, with an intact tympanic membrane and middle ear cavity, intranasally deposited bacteria cause AOM and how tympanic membrane stimulation influences this procedure. STUDY DESIGN: In vivo, murine model. METHODS: In a rat model, Streptococcus pneumoniae, type 3, was intranasally inoculated for 5 consecutive days. The tympanic membrane was treated with saline or with compound 48/80 or was left untreated. The development of AOM was evaluated by otomicroscopy, light microscopy, and middle ear culture. RESULTS: Ninety percent of the ears developed AOM. However, when the tympanic membranes were treated with saline or compound 48/80, only 40% and 57%, respectively, developed AOM. In all, 23 of 40 ears developed AOM and 20 ears showed growth of bacteria. CONCLUSION: Repeated intranasal deposition of S. pneumoniae, type 3, causes AOM in the rat. The development of AOM can be influenced by tympanic membrane stimulation.     

Partial oxygen tension of middle ear cavity in a normobaric environment

The present theory of eustachian tube function and middle ear ventilation posits that oxygen absorbed by the middle ear mucosa causes negative middle ear pressure which is relieved by periodic opening of the eustachian tube during swallowing and yawning. Measured by a PO2 sensor (Clark type) inserted into the middle ear cavity of normal adults through the eustachian tube, the partial oxygen pressure of the tympanic cavity was found 53.7 +/- 6.5 Torr (N:22). It was about one-third of ambient pressure (about 150 Torr), and showed no change when the eustachian tube was opened by swallowing. Our second study measured the effect of alterations in the systemic arterial blood oxygenation on middle ear gas exchange in 23 guinea pigs ventilated using 21% (room air), 50%, 70% and 100% oxygen at constant carbon dioxide blood gas tension. Partial oxygen tension (PO2) of middle ear cavity was measured by inserting a PO2 sensor into the tympanic bulla through a bore hole. The following results were obtained: (1) PO2 of the middle ear cavity was 39.3 +/- 2.2 Torr at room air, 42.2 +/- 0.84 Torr at 50%, 46.6 +/- 1.1 Torr at 70% and 54.5 +/- 3.7 Torr at 100% oxygen breathing. (2) There was a significant correlation between PO2 of the middle ear cavity and systemic arterial hyperoxygenation noted. Y = 30.79 + 0.056.X (r = 0.9440) (3) The rate of oxygen diffusion in the middle ear cavity was 2.665 x 10(-5) ml/min/cm2 and the rate of oxygen absorption in the middle ear space was 2.874 x 10(-5) ml/min/cm2. No significant difference between the rate of diffusion and that of absorption of oxygen in the middle ear cavity was noted. In our third study, electron microscopy shows that the submucosal capillaries of the human mastoid cells are structures which facilitate the intra- and extravascular transport of substances. It is known from these results that tympanic cavity pressure is kept equal to ambient pressure, or slightly higher to atmospheric pressure, by the respiratory function of the middle ear and mastoid cells so that outflow of air from the tympanic cavity to the pharyngeal orifice occurs during the ventilation of the eustachian tube at ambient pressure and inflow of air from the pharynx to the tympanic cavity is prevented in the absence of environmental pressure changes. The middle ear cavity has respiratory function, and in particular, such function of the mastoid cavity, which is larger in volume than the tympanic cavity, plays a significant role.(ABSTRACT TRUNCATED AT 400 WORDS)     

Experimental induction of middle ear cholesteatoma in rats

We induced cholesteatoma in two groups of rats by instilling different concentrations of propylene glycol into the middle ear cavity. Fifteen rats were exposed to 50% propylene glycol (group I), while pure propylene glycol was applied to six others (group II). The group I rats were killed 1 month after instillation. Seven of the 15 showed cholesteatoma in the middle ear with accumulation of keratin debris. The group II rats were killed 3 months after instillation. All six animals showed inflammation in the experimental ears, and five of the six experimental ears showed cholesteatoma in the middle ear cavity. Six experimental ears in group I and five in group II revealed retraction of the tympanic membrane, possibly due to eustachian tube obstruction. Bone resorption was seen along with cholesteatoma and inflammatory cells and osteoclasts in the middle ear of all 11 of these rats. The seventh cholesteatoma of group I can be classified as a microcholesteatoma, a pearl-like cyst within the tympanic membrane. The microcholesteatoma was formed by an invasion of basal cells from the tympanic epidermis and the proliferation of these cells in the fibrous layer of the tympanic membrane. Our findings suggest that cholesteatoma in the middle ear cavity is a response to the inflammation produced by high concentrations of propyleme glycol.     

Tympanometry and laser Doppler interferometry measurements on otitis media with effusion model in human temporal bones.

HYPOTHESIS: The aim of this study is to investigate the effect of middle ear fluid and pressure on tympanic membrane mobility by using laser Doppler interferometry and to compare these results with tympanometry. BACKGROUND: Tympanometry has been commonly used for evaluation of otitis media with effusion, a middle ear disease with fluid in the cavity. However, this test lacks specific interpretations of middle ear disorders based on tympanometric data. Laser interferometry, as an advanced research tool to measure middle ear function, may provide knowledge of how tympanic membrane mobility is affected by middle ear fluid and pressure. METHODS: An otitis media with effusion model was created in seven human temporal bones for conducting experiments with tympanometry and laser interferometry. Middle ear pressure varied from -20 to +20 cm water, and the amount of fluid in the middle ear was gradually increased to fill the cavity. RESULTS: The displacement of the tympanic membrane measured by laser interferometry at selected frequencies decreased significantly corresponding to the middle ear air pressure changes. Tympanometry detected middle ear pressure by the change of tympanometric peak location, but the tympanogram shape was not affected by the middle ear pressure. The middle ear fluid was detected by tympanometry with as little as 0.3 mL, and laser interferometry was able to measure the displacement change of the tympanic membrane with 0.2 or 0.3 mL fluid at different frequencies. CONCLUSION: Laser interferometry can detect the effect of middle ear pressure and fluid on tympanic membrane movement as well as tympanometry does.     

Pathogenesis of experimental aural cholesteatoma in the chinchilla

Histopathological observation of celloidin serial sections of the chinchilla middle ear after treatment with propylene glycol disclosed the development of severe inflammation of the middle ear mucosa and tympanic membrane, papillary proliferation of the epidermis of the tympanic membrane and external auditory meatus, and retraction and adhesion of the tympanic membrane. The findings for the tympanic membrane, impedance testing and histopathological examination suggested that there were two types of acquired cholesteatoma formation, probably with a difference in the pathogenesis. In one type, the proliferated epidermal layer of the tympanic membrane penetrated into the middle ear cavity making tympanic perforations. In the other type, there was progressive retraction of the tympanic membrane forming a retraction pocket. We discuss the two different patterns of cholesteatoma development.     

Application of platelet-enriched plasma for the prevention of cochleovestibular disorders associated with piston stapedoplasty

The present study was designed to evaluate the influence of sealing the labyrinthine vestibule with platelet-enriched plasma (PEP) on the development of cochleovestibular complications following piston stapedoplasty. The platelet-rich plasma was prepared by single-step centrifugation of the whole venous blood. Analysis of the data obtained showed that the use of PEP for sealing the periprosthetic space after stapedoplasty reduces the risk of development of sensorineural hearing impairment compared with the application of fatty tissue for the same purpose or a freely positioned prosthesis. Moreover, the use of PEP decreases the probability of the development of tympanophonia and its intensity after piston stapedoplasty.     

Type I allergic reactions of the middle ear and eustachian tube: an experimental study

To clarify the role of type I allergic reactions in etiology and pathogenesis of otitis media with effusion and to determine whether or not the middle ear is an allergic "shock" organ, we made animal models of nasal allergy in guinea pigs by passive sensitization with serum of homologous animals containing specific IgE antibodies. We also examined the eustachian tube, tympanic cavity (histologically), and tubal function after the induction of type I allergic reactions of the nose. However, the involvement of histologic changes was limited only up to the area near the pharyngeal orifice. The tubal dysfunction evoked by nasal allergic reactions was transient, culminating in no middle ear effusion. Upon direct antigen-challenge into the tympanic cavity, allergic changes were observed in the mucosa lining the tympanic bulla, even though no microscopic effusion was present. Findings of the present study suggest that type I allergic reactions of the nose are not an etiologic factor for otitis media with effusion, although the middle ear is potentially an allergic shock organ.     

Anterosuperior anchoring myringoplasty using cyanoacrylate glue can prevent packing gelfoam in the middle ear cavity

ObjectivesAlthough a number of methods have been attempted to improve securing the graft, packing gelfoam in the middle ear cavity cannot be avoided, which could obstruct the tympanic ostium of the Eustachian tube and affect inner ear function. Myringoplasty using tissue adhesive has gained traction because tissue adhesives can effectively stabilise the graft and act as scaffolding to improve the graft uptake. The aim of this prospective study was to explore myringoplasty using cyanoacrylate glue with no packing in the middle ear cavity for the repair of subtotal tympanic membrane (TM) perforations.MethodsBetween March 2014 and November 2015, 71 patients with subtotal TM perforations were randomly and prospectively divided into a glue group and a control group. Two securing techniques were performed using only cyanoacrylate glue or using only filling gelfoam in the middle ear cavity, respectively, during an anterosuperior anchoring myringoplasty operated by a single surgeon.ResultsAt a 6-month follow-up, the graft uptake rate was 87% in the glue group and 89% in the control group. A significant hearing improvement was found in both groups postoperatively when compared to the preoperative values (P < 0.05 for both). There was no significant difference in the graft uptake rate and hearing improvement between the 2 groups (P > 0.05). Similar complications were found in each group.ConclusionCyanoacrylate glue is a helpful material for graft stabilisation and can substitute for filling gelfoam in the middle ear cavity during anterosuperior anchoring myringoplasty for subtotal TM perforation.     

Usage of platelet-enriched plasma as hemostatic and analgenic medication in tonsillectomy

The rate of posttonsillectomy hemorrhage, pain severity were assessed in the study group (80 tonsillar niches) and in the control group (110 tonsillar niches). Treatment of postoperative tonsillar niches with platelet-enriched plasma (PEP) was performed in the study group and was not performed in the controls. No hemorrhage was registered in the study group and 9 cases of hemorrhage occurred in the control group. Swallowing test and analysis of the visual-analogue scales demonstrated that pain after tonsillectomy was less severe after local use of PEP. Thus, usage of PEP in the region of the postoperative wound is effective in prevention of hemorrhage and pharyngeal pain attenuation after tonsillectomy.     

Effects of otic drops on chinchilla tympanic membrane

Experimental studies have shown that if antibiotic otic drops reach the middle ear cavity they produce severe inflammation. However, the effects of these preparations on the tympanic membrane have not been thoroughly investigated. This study was designed to assess morphological changes in the chinchilla tympanic membrane two to 21 days after a single 0.2-mL application of an antibiotic otic preparation (Cortisporin Otic Suspension) to the middle ear cavity. At two days, the epidermal and the mucosal layers were destroyed. By four days, reepithelialization had occurred and all layers of the tympanic membrane subsequently became markedly hyperplastic. Disruption of the fibrous layer, invasion of keratinizing epidermis to the medial surface, and perforation were observed at three weeks. These findings indicate that tympanic membrane damage is a potentially significant aspect of the ototoxic properties of topical otic preparations.     

First forty-eight hours of developing otitis media: an experimental study

The early inflammatory changes in the tympanic membrane were explored in 2 rat models. Acute otitis media was induced by instillation of Streptococcus pneumoniae type 3 into the middle ear cavity, and otitis media with effusion was induced by blockage of the eustachian tube. Otomicroscopic examination was performed before the rats were painlessly sacrificed at 3, 6, 9, 12, 18, 24, or 48 hours after initiation of the otitis media conditions. The tympanic membrane was studied by light and electron microscopy. Both acute otitis media and otitis media with effusion caused early inflammatory changes of the tympanic membrane, and the pars flaccida was the portion that reacted first. The inflammatory alterations were most pronounced in the acute otitis media model. The course of inflammation showed a bimodal pattern with an early deposition of a filamentous material with a band pattern, typical of fibrin. Despite a fluid-filled middle ear cavity, the inflammatory changes in the otitis media with effusion model were moderate, as was consistent with the clinical appearance of the tympanic membrane.     

In vitro reconstruction of a three-dimensional middle ear mucosal organ and its in vivo transplantation

CONCLUSIONS: These experimental findings suggest the feasibility of artificial middle ear mucosa grafting as an effective treatment for achieving mucosal regeneration after middle ear surgery. OBJECTIVES: Postoperative mucosal regeneration of tympanic cavity and mastoid cavity is of great importance after middle ear surgery. We reconstructed in vitro a three-dimensional middle ear mucosal organ, and assessed its feasibility for regenerative medicine of middle ear-related diseases. MATERIALS AND METHODS: Epithelial cells and fibroblasts were isolated from the middle ear mucosa of rats and propagated by subculturing. An artificial middle ear mucosal organ was reconstructed by overlaying the middle ear epithelial cells on three-dimensional lattices of a collagen gel that had been repopulated with the fibroblasts. In addition, the artificial organ was implanted in the middle ear cavity of rats. RESULTS: The artificial middle ear mucosa consisted of the single layer of epithelial cells, the basal membrane, and the underlying connective tissue. Electron microscopy revealed the presence of tight junctions and adherence junctions on the apical side, and adhesion complexes made of desmosomes. The reconstituted mucosa expressed genes of mucin, strongly suggesting that the artificial middle ear mucosa was capable of secreting mucus proteins. The DiI-labeled artificial middle ear mucosa implanted into the middle ear cavity was well engrafted and associated with host tissues.     

中耳内窥镜解剖

目的 :探讨经不同途径的中耳内窥镜解剖所见。方法 :采用 0°,30°,90°的硬质内窥镜 ,对 17个颞骨标本进行了观察 (其中干标本 6个 ,湿标本 11个 ) ,内窥镜插入途径有 :外耳道 ;耳后切口 (包括乳突腔 鼓窦和乳突腔 后鼓室两条亚途径 ) ;中颅窝。结果 :外耳道途径 :采用 0°,30° ,90°的硬质内窥镜 ,所有鼓室结构都可看见 ,包括鼓室窦、面隐窝、上鼓室前隐窝等隐蔽处 ;乳突腔 鼓窦途径 :可以看见乳突腔、鼓窦、上中鼓室等结构 ;乳突腔 后鼓室途径 :可观察到乳突及中下鼓室结构 ;中颅窝途径 :可以观察到上鼓室、鼓窦、乳突腔及鼓室外侧壁的结构 ,中鼓室的大部分结构亦可观察到。结论 :经不同的途径行内窥镜术能清楚地观察到中耳各个结构 ,因此能减少胆脂瘤的复发率及评价术后中耳腔的状态 ,其中 30°的内窥镜提供的视野较好 ;但如经外耳道途径观察后上鼓室及经乳突腔 鼓窦途径观察后鼓室 ,则 90°内窥镜较适合     

The use of Proplast in experimental middle ear surgery

The results of the use of Proplast, a new alloplastic material, in experimental middle ear surgery are described. This material was tested for cavity obliteration, closure of bony defects and as a columella between the tympanic membrane and the medial wall of the middle ear. Proplast was well tolerated in the middle ear cavity even in cases with inflammation of the middle ear. The implants were integrated within the recipient tissue by fibrous ingrowth occurring within one week. Bony ingrowth was observed in those cases where the implant contacted the bony wall within 3 weeks. Proplast which supported the tympanic membrane was infiltrated by fibrous tissue and incorporated in the lamina propria. No significant side effects were observed in a 6-month follow-up period although a possible influence on bone remodelling could not be fully excluded.     

The release of histamine from the pars flaccida mast cells one cause of otitis media with effusion?

In this experimental study in the rat, compound 48/80--a potent degranulating drug of mast cells--was instilled in the external auditory meatus towards the tympanic membrane. Moreover, effusion material was produced in the attic space by blocking the tympanic isthmus with a piece of Gelfoam applied through the tympanic bulla. Both these procedures caused a degranulation of the pars flaccida mast cells and subsequently histamine was detected in the rinsing fluid collected from the middle ear cavity. A possible direct cause of the effusion material in the middle ear cavity may be a degranulation of the pars flaccida mast cells, thus resembling an allergic reaction Type I.     

Ototoxic effect of quaternary ammonium compounds

In earlier investigations by the author it has been shown that chlorhexidine, when introduced into the middle ear of guinea pigs, caused serious damage to the inner ear. The present investigation was performed in order to study if the quaternary ammonium compounds benzethonium chloride and benzalkonium chloride, frequently used for skin disinfection, can also induce inner ear damage when introduced into the tympanic cavity of guinea pigs. The disinfectants in question, at a concentration of 0.1% and in a solution of aqua dest. or 70% alcohol, were introduced into the animals' middle ear for exposure times of 10, 30, or 60 min. The animals were sacrificed 2 or 9 weeks after the exposure and the organ of Corti and vestibular neuroepithelia were studied as surface preparations with phase contrast microscopy. It was found that most of the ears exposed to the disinfectants had suffered damage, affecting both the vestibular and cochlear parts of the inner ear. The extent of the damage was related both to the duration of exposure and to the length of the animals' survival after the exposure. Furthermore it was found that the tympanic cavity and the perilymphatic spaces of vestibulum and cochlea were pathologically changed.     

Transcanal endoscopic treatment of benign middle ear neoplasms

The application of endoscopic surgery for middle ear pathologies is rapidly increasing. At present, its main application is in the treatment of middle ear cholesteatoma. This report describes the application of this technique as treatment for some benign lesions that may involve the middle ear cleft. A retrospective chart review of six patients who underwent exclusive endoscopic tympanic cavity surgery for benign neoplasms was performed between November 2011 and January 2012. Based on charts, images, and surgical reports, data from the patients were summarized for further consideration. All of the six lesions were in the tympanic cavity without involvement of the mastoid region. An exclusive endoscopic transcanal approach was used in all cases. No patient showed signs or symptoms of pathology recurrence. Endoscopic transcanal excision of benign tympanic cavity neoplasms represents a safe procedure, with minimal morbidity and without external incisions or mastoidectomies.